THE EFFECT OF SALINITY ON THE GROWTH OF THE HALOPHYTE ATRIPLEX HORTENSIS (CHENOPODIACEAE)

The effect of salt stress on the growth of the Atriplex hortensis was determined by growing plants in soils receiving a one-time irrigation of nutrient solution containing low, medium, and high levels of NaCl. Atriplex plants were grown in sand culture under controlled greenhouse conditions. The experiment was compared to two varieties of A. hortensis. Growth and yield were progressively declined by increasing NaCl concentrations. Atriplex hortensis, an annual halophyte, exhibits significant reduction in height and biomass under saline stress conditions. The photosynthetic activity decreases when plants are grown under saline conditions leading to reduced growth and productivity. Low levels of salinity ( 5 g/l NaCl) did not cause substantial inhibition of growth but increasing concentrations of salt induced a progressive decline in length and weight of the plants. Salt stress induced a significant decrease in leaf area, but it had no significant effect on leaf water content. The results of present study indicate no differences in salinity tolerance in both Atriplex plants. Another possible conclusion is that improved tolerance to salt stress may be accomplished by decline in growth and photosynthetic activity. Based on these findings the tolerant Atriplex can be grown in moderately NaCl-contaminated soils.